This work reports a relatively rapid procedure for the forecasting of the remediation time (RT) of sandy soils contaminated withcyclohexane using vapour extraction. The RT estimated through the mathematical fitting of experimental results was compared with thatof real soils. The main objectives were: (i) to predict the RT of soils with natural organic matter (NOM) and water contents different fromthose used in experiments; and (ii) to analyse the time and efficiency of remediation, and the distribution of contaminants into the soilmatrix after the remediation process, according to the soil contents of: (ii1) NOM; and (ii2) water. For sandy soils with negligible claycontents, artificially contaminated with cyclohexane before vapour extraction, it was concluded that: (i) if the NOM and water contentsbelonged to the range of the prepared soils, the RT of real soils could be predicted with relative differences not higher than 12%; (ii1) theincrease of NOM content from 0% to 7.5% increased the RT (1.8–13 h) and decreased the remediation efficiency (RE) (99–90%) and (ii2)the increase of soil water content from 0% to 6% increased the RT (1.8–4.9 h) and decreased the RE (99–97%). NOM increases the monolayercapacity leading to a higher sorption into the solid phase. Increasing of soil water content reduces the mass transfer coefficientbetween phases. Concluding, NOM and water contents influence negatively the remediation process, turning it less efficient and moretime consuming, and consequently more expensive.
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